Systems to detect the presence of a child in a child seat have been developed and tested where the sensing systems are integrated directly into the child seat structure, as indicated in recent NHTSA report (DOT HS 812 187, July 2015). These systems are based on detection of the child seat through several sensing mechanisms, including the measurement of pressure, force, latching clip detection, etc. Such systems are designed to include electronics within or on the seat for detection and communication to/from the vehicle and/or to/from cell phones. The systems contain microprocessors that take the sensor and vehicle information as inputs, and monitor conditions where the child may be left behind, and a range of potential countermeasures can be taken, including initiating a warning through the vehicle systems (e.g. horn alarm); modifying the vehicle cockpit (e.g., reducing/increasing cabin temperature); and initiating a warning through telematics (e.g., sending a warning to the parent/driver).
Additionally, detection of child seat occupancy has been studied using a two-dimensional (2-D) camera, a three-dimensional (3-D) camera and other active electromagnetic methods such as ultrasonic, radar, and acoustics. These systems have shown the potential to detect the child seats and classify them as occupied or un-occupied. Another potential method is based on the use of seat weight detection systems, possibly including belt tension sensor(s). All of the above methods can be prone to incorrect classifications, due to clothing, due care, blocking obstructions, lack of motion by the occupant, etc. Moreover, many of these systems depend on sensing an expected location of an occupant, and cannot account for an occupant being separated from the sensed location.